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SAMUELVW. HUDSON, 0F BAVER MEA'DW. PENNSYLVANIA.

Letters Patent No. 68,879, dated September 17, 1867.

IMPRVEMENT IN STEAM-ENGINE SLIDE-VALVES.

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TO ALL WHOM IT MAY CONCERN l n,

Be it known that I, SAMUEL W. HUDSON, of Beaver Meadow, in the county of Carbomand State of Pennsylvania, have invented a new and useful Improvement in Slide-Valves; and I doA hereby declare the following i to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, which are made part of this specification.

This invention consists in the construction of a slide-valve, with a wing projecting downward from its sole, i

whereby to operate the valve mainly from the exhaust steam. It further consists in a duplex arrangement of the steam-passages of the valve, whereby the valve when actuated is moved in the Isame direction as the piston. l

Figure 1 is a plan partly in section 'of a steam-chest and slide-valve constructed according to my invention.

Figure 2 is a vertical longitudinal section of the same, the planes of section being indicated by the lines` i xx, iig. 1. v

Figure 3 is a vertical transverse section oi' the same, the line yy, tig. 2, indicating the planeofsection.

Similar letters of reference indicate corresponding parts in the several figures. l

A'is a steam-chest; A1 the steam-port conveying steam thereto; A2 the exhaust-port; and AiA the channels, which convey steam to either end of the cylinder and conduct it therefrom, in customary manner. B B is a duplex slide-valve, from the sole of which a wing, B1, projects downward into the cavity or chamber C, which is formed below the valve-chest, and just above the exhaust-port A2 with which it is in communication. The construction o' the valve will be best understood by the aid of fig. 2. The two distinct parts B B of the valve are separated by the central partition B5, of which the wing Bl is but a-continuation. Each part B has two steam-passages, 12616263, respectively.' The passages bl b3 extend archwise over the central` portion bi of the sole of each part B of the valve, and either vone or the other of these passages is always in av position to afford communication between one ot' the channels A3 A* and the exhaust-port AL'. In like manner either one or the other oi' the passages b b2 is always in a position to ai'ord commnnication'between the steam-portA1 and one of the channels A3 A4. D is the valve-rod'working through a suitable stuffing-box, E, and having a suitable tappct connection with the piston which gives the valve an impulse in the direction of the pistcns movement when said piston is about to complete its stroke.

In order to explain `the operation, let it be supposed that the pis-ton is moving in the direction of the arrows 12, and that theposition of the valve is such as represented in fig. 2. Such being the case,`the course of the live steam from the stcamort Al is down throurh the central assawe into channel A3, which conducts it P P e D into the cylinder; and the course of' the exhaust steam is through the channel A", passage b3, chamber C, and

thence through the exhaust-port A2. Under this position of the valve it will be observed that bothends of the` passage b1, as also the lower end of passage 112, are closed by the bottom of the steam-chcst upon which they rest. The piston, when about to complete its motion in the direction above indicated, actuatesthevalve through the tappet connection, so as te move the valve in the same direction, thereby placing the passage bzin communication with channel A", and the passage b in communication with channel A3 and Vchamber 0. `The motion which the valve thus derives directly from4 the piston is merely suflicient to opena contracted passage-way between one end of 6'* and A3, and the other end of' b and C, the remainder and greatest proportion of the valves motion being effected bythe action of the exhaust steam upon the wing B, such steam expanding in chamber C, between the wall C and the wing or projection Bl. By this action of the-exhaust steam on its way to the exhaust-port A2, the motion of the valve necessary to effect its reversal is'complctcd, such motion of course terminating' when the wing B1 reaches the wall Chef the chamber C. Returning, the` piston, near the completion of itsstroke, again gives the valve its initial movement, when the passage b3 conveys exhaust steam fromA4 to C, wherein the steam acting against the wing B and the wall C2 moves the valve to thejposition shown in fig. 2. In order to equalize thc steam pressure upon the valve the passages 662 and b' b3 are -situated at diagonally opposite positions of the valve, as seen ingfl.

Having thus described my invention, .what I claim as new, and desire to, secure by Letters Patent, is-

1. The wing Bl projecting from a slide-valve to move it by the action of steam, substantiallyas described.4

2. The arrangement of the steam-passages b b Zbs', substantially as and for the purpose specified.

To the above specication of my invention I have signed my hand this 20th day of June, 1867.

' SAMUEL W. HUDSON.

Witnesses: i g l Ocr'AvrUs KNIGHT, JAMES LrEw'm. 

